US2797648A

US2797648A - Automatic "kick-off" rocking means for gas lift well

Info

Publication number: US2797648A
Application number: US329565A
Authority: US
Inventors: Paul G Carpenter
Original assignee: Phillips Petroleum Co
Current assignee: Phillips Petroleum Co
Priority date: 1953-01-05
Filing date: 1953-01-05
Publication date: 1957-07-02
Anticipated expiration: 1974-07-02

Description

July 2, 1957 P. G. CARPENTER AUTOMATIC "KICK-OFF" ROCKING MEANS FOR GAS LIFT WELL Filed Jan. 5, 1953 INVENTOR. P. G.CARPENTER BY AT TORN EYS AUTOMATIC KICK-OFF ROCKING MEANS FOR GAS LIFT WELL Paul G. Carpenter, Bartlesville, Okla., assignor to Phillips Petroleum Company, a corporation of Delaware Application January 5, 1953, Serial No. 329,565 8 Claims. (Cl. 103-232) This invention relates to a process and apparatus for automatically rocking a gas lift well to initate fluid flow therein. A specific embodiment of the invention pertains to a device and process for automatically kickingoff or reversing the rocking means in a gas lift well.

The gas lift method of flowing deep wells, particularly oil wells, is well known in the art and is set forth in U. S. Patent 1,740,105. By alternately applying gas pressure to the liquid surface in the well inside the tubing and outside thereof the rise of the liquid inside of the tubing eventually becomes great enough to lower the level of the liquid on the outside of the tubing to the level of the end of the tubing so that the pressuring gas is forced up the tubing and thereby atomize the oil therein and form a froth or emulsion which greatly decreases the weight of the hydrostatic head inside the tubing so that the pressurizing gas eventually raises the froth or emulsion inside the tubing to the well head where it can be drawn off in continuous flow.

It should be obvious that reversing the gas pressure from the well tubing to the well casing and vice versa should be effected at the instant at which the fluid in the tubing reaches its maximum height in any particular cycle of operation and also when the fluid in the casing (outside of the tubing) reaches its maximum height at the opposite phase of the cycle. It is particularly diflicult to hand-operate the valves which control the flow of pressurizing gas into the casing and tubing of the well and also the flow of fluid from the well once the flow has reached the well head.

The principal object of the invention is to provide an apparatus and process for automatically rocking a gas lift well. Another object of the invention is to provide means and method for automatically reversing or kicking off the flow of pressurizing gas into and out of the well tubing and casing at the moment the fluid in the well reaches the maximum and minimum levels. A further object of the invention is to provide means and method of synchronizing the flow of pressurizing gas into and out of the well with fluid flow out of the tubing from the well head. Other objects of the invention will become apparent from a consideration of the accompanying disclosure.

A complete understanding of the invention may be had by referring to the accompanying drawing which shows diagrammatically across-sectional view of one modification of apparatus which may be utilized to accomplish the objects of the invention. Referring to the drawing, a well casing 10 extends into the earth and contains a body of oil or other liquid and well tubing 11 through which the flow of fluid is to be induced. A conduit 12 extends from the well head to a gas flow reversing mechanism or valve 14. A gas pressure supply line 16 enters the cylindrical side of the control valve 14 at a point midway between the ends of the cylinder. A pair of spaced-apart, close-

fitting pistons

17 and 18 on a connecting rod 19 effect the reversing of flow of gas to and from the well tubing and casing when the connecting rod and its pistons are reciprcated in the cylinder. Cylindrical control valve 14 is also provided with

outlets

21 and 22 at either end of the cylinder. A valve 23 merely allows for shutting off the pressure or flow of gas into the system.

The connecting rod and its attached pistons in control valve 14 are operated or reciprocated by device 26 which contains a fluid-operated piston 24. Close-fitting piston 24 reciprocates in the cylinder of device 26 and is actuated by either gas or liquid alternately introduced to the ends of the cylinder through

lines

27 and 28. A fourway reversing valve 31 is arranged in communication with

lines

27 and 28 so that by reversing element 32, gas or liquid from supply line 33 is alternately passed to

lines

27 and 28 and the exhaust gas is passed out through line 34.

Channels

36 and 37 in reversing device 32 are arranged so that by moving reversing device 32 through pressure from the fluid in line 33 is applied alternately to opposite sides of piston 24 to produce the reciprocation desired.

A diaphragm control element 38 is positioned between

conduits

12 and 13 and is in communication therewith through

conduits

42 and 43. The diaphragm control element contains a diaphragm 39 and an actuating arm 41 which is in actuating communication by means of a linkage 40, which may be mechanical or pneumatic, with the operating arm or lever of reversible valve 31.

A fluid check valve 44 in line 13 prevents the flow of oil to control valve 14 or diaphragm 38 but allows free flow of pressurizing gas therethrough A control valve 46 in tubing 11 downstream of the juncture of conduit 13 with tubing 11 is operated by mechanical linkage 47 with piston rod 19 so as to close when the connecting rod moves to the left and opens when the connecting rod moves to the right.

The apparatus of the drawing as described above operates to automatically reverse the flow of gas through

conduits

12 and 13 and thereby through casing 10 and tubing 11 at the exact time at which the fluid in the tubing or in the casing reaches its maximum height on any particular cycle of rocking. Diaphragm control 38 is sensitive to pressure diflerential between

conduits

12 and 13, and is set to reverse valve 31 when maximum pressure differential is registered on diaphragm 39. Reversing device 32 of valve 31 is rotated through 90 so as to reverse the flow of fluid from pressure line 33 to reciprocating device 26 when maximum pressure differ-- ential is reversed in diaphragm control 38. As shown in the drawing, valve 31 admits gas to the lefthand side of piston 24 which causes the reversing mechanism in control valve 14 comprising

pistons

17 and 18 to move to the right. Under this condition gas is admitted to the fluid between the casing and tubing so as to force the fluid therebetween downward. When the gas has forced the oil up the tube to its highest point a maximum pressure is applied to the right side of diaphragm 39, causing it to rotate valve A 90 by means of mechanical linkage 40. The result of this action causes the gas to be supplied to the right side of piston 24, thereby energizing device 26 and moving the control mechanism in valve 14 to the left. This movement of the control mechanism in valve 14 to the left admits pressurizing gas from line 16 to conduit 13 so that the gas pressure is applied to the fluid in the tube thereby forcing the same downward. Simultaneously, gas from the casing outside of the tubing is vented through outlet 22 in valve 14. In this phase of the cycle valve 46 is closed by the movement of connecting rod 19 to the lift so that all of the pressurizing gas is forced down into the well through tubing 11. Valve 46 is then opened when control valve 14 is moved to the right. It will thus be apparent that the switching through valve 46.

After initiation of oilfio'w in wen tubing 11 th rough valve 46, it is desirable to immediately stop the operation of control valve 14 in the position shown in the drawing 1 so that pressure gas continually passes from line 16*to line 12 into the well casing thereby continuously forcing atomized oil out of the well through the tubing; This may be accomplished in various ways, e. g., by shutting olf the flow of fluid in line 33 When oil'fiows in the production line below valve 46 and restoring flow in line 33 when oil ceases to flow in the production line so as to again set into operation the automatic rocking mechanism.

Hand operated valves may also be used to stop the action of the rocking mechanism so as to continue the flow of oil out of the tubing. e

Various modifications of the apparatus and process described are within the scope of the invention. The reversing valve 31 may be of any convenient type and need not be limited to a 4-way valve. Likewise, reciprocating mechanism 26 may be any type which can be conveniently reversed by the movement of mechanical linkage 40 in response to maximum fluctuation of diaphragm 39.

Certain modifications of the invention will become apparent to those skilled in the art and the illustrative details disclosed are not to be construed as imposing unnecessary limitations on the invention.

I claim:

1. Apparatus for rocking a gas lift well to initiate flow which comprises in combination, a pair of conduits, one adapted to communicate with the tubing and the other with the casing of a well; a gas pressure supplyline adapted to feed alternately into said conduits thru the hereinafter defined control valve; a control valve connecting said supply line with said pair of conduits; control means in said valve for directing the flow of gas first to one and then to the other of said pair of conduits, singly; a conduit communicating between said pair of conduits; a pressure sensitive diaphragm in said conduit; reversible actuating means for said control means; and a reversing device sensitive to the movement of said diaphragm and in actuating communication with said reversible actuating means.

2. The apparatus of claim 1 wherein one of said conduits is operatively connected to a well tubing and the other to a well casing.

3. Apparatus for rocking a gas lift well to initiate flow which comprises in combination; a control valve comprising a cylinder including a pair of spaced-apart close-fitting reciprocating pistons on a connecting rod, an outlet adjacent each end oflsaid cylinder, and a gas pressure supply inlet disposed intermediate the ends of said cylinder; a first conduit connected with said cylinder ata point intermediate said inlet and one of said outlets, said first conduit being adapted to connect with the casing of a well; a second conduit connected with said cylinder at a point intermediate said inlet and the other of said outlets, said second conduit being adapted to connect with the tubing of said well; a diaphragm control connecting said first and second conduits, being sensitive to the fluid pressure differential between same; reciprocating means 'for said connecting rod and pistons; and means for reversing said reciprocating means in response to maximum pressure differential in said diaphragm control.

4. The apparatus of claim 3 wherein said second con duit is operatively connected to a well tubing and said first conduit is operatively connected to a well casing.

5. Apparatus for rocking a gas lift well to initiate flow which comprises in combination a control valve comprising a cylinder including a pair of spaced-apart closefitting reciprocating pistons on a connecting rod extending thru at least one end of said cylinder, an outlet adjacent each end of said cylinder, andra gas pressure supply inlet disposed intermediate the ends of said cylinder; a first conduit adapted to connect the casing of a well with said cylinder at a point intermediate said inlet and one of said outlets; a second conduit adapted to connect the tubing of said well with said cylinder at a point intermediate said inlet and the other 'of said outlets; a diaphragm control connecting said first and second conduits, being sensitive to the fluid pressure differential between same; reciprocating means on an extended end of said connecting rod comprising a fluid actuated piston and a close-fitting cylinder around said piston, a fluid inlet and outlet in each end of said close-fitting cylinder, and a reversible valve connected with said inlets and outlets and with a fluid supply line for reversing flow of fluid into and out of said cylinder; and means connecting said diaphragm with said reversible valve adapted to reverse same in response to maximum pressure differential on said diaphragm.

6. The apparatus of claim 5 wherein said second conduit is operatively connected to a well tubing and said first conduit is operatively connected to a well casing.

7. Apparatus for rocking a gas lift well to initiate flow which comprises in combination, a well having tubing and easing; a painof conduits, one communicating with said tubing and the other with said casing; a gas pressure supply line adapted to feed alternately into said conduits thru the hereinafter defined control valve; a control valve intermediate connecting said supply line with said pair of conduits; control means in said valve-for directing the flow of gas first to one and then to the other of said pair of conduits, singly; a conduit communicating between said pair of conduits; a pressure sensitive diaphragm in said conduit; reversible actuating means for said control means; and a reversing device in actuating communication between said diaphragm and said reversible actuating means; a take-01f conduit from said well tubing hav ing a shut-off valve therein downstream of the aforesaid conduit communicating with said tubing; actuating means for said valve responsive to the movement of said control means adapted to close said shut-off valve when gas is being directed into said tubing and open same when gas is being directed into said casing.

8. Apparatus for rocking a gas lift well comprising in combination a well having a casing and a tubing; a first conduit connected with said tubing; a second conduit connected with said casing; means connected with said first and second conduits for alternately introducing a pressurizing gas into one and then the other of the conduits and simultaneously exhausting gas from the conduit other than the one to which gas is being introduced; a pressure sensitive device connected across said conduits and operatively connected with aforesaid means; and a pressurizing gas supply line connected with aforesaid means.

References Cited in the file of this patent UNITED STATES PATENTS UNITED STATES PATENT OFFICE CERTIFICATE OF common Patent No. 2,797,648 July 2, 1957 Paul G. Carpenter It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Let oers Patent should read as corrected below.

Column 4, line 36, before "connecting" strike out intermediate Signed and sealed this 31st day of December 1957.

(SEAL) Attest:

KARL LINE ROBERT c. WATSON Atteeting Officer Canmissioner of Patents

Claims

8. APPARATUS FOR ROCKING A GAS LIFT WELL COMPRISING IN COMBINATION A WELL HAVING A CASING AND A TUBING; A FIRST CONDUIT CONNECTED WITH SAID TUBING; A SECOND CONDUIT CONNECTED WITH SAID CASING; MEANS CONNECTED WITH SAID FIRST AND SRCOND CONDUITS FOR ALTERNATELY INTRODUCING A PRESSURIZING GAS INTO ONE AND THEN THE OTHER OF THE CONDUITS AND SIMULTANEOUSLY EXHAUSING GAS FROM THE CONDUIT OTHER THAN THE ONE TO WHICH GAS IS BEING INTRODUCED; A PRESSURE SENSITIVE DEVICE CONNECTED ACROSS SAID CONDUITS AND OPERATIVELY CONNECTED WITH AFORESAID MEANS; AND A